Is there a way to change the default Booean operation type?
This has been asked before in 2015: Where are the modifier scripts in the Blender package contents folder?
They are part of the main app coding, so unless things have changed, not easily modified.
I would like to do this, too, as I use Booleans a lot for 3D print drawing.
Not changing dimensions from millimetres to CM would be good as well.